Pipe cutter



Patented Nov. 27, 1923.

NTD STATES PATENroFI-1c1-:.

HARRISON H. EATON, OF BEVERLY, MASSACHUSETTS.

PIPE CUTTER.

Application filed July 8, 1922. Serial No. 573,579.

' Pipev Cutters, of-which the following is a specification.

This invention relates to hand operated implements for cutting pipe and more particularly to devices of the general type disclosed in the patent to Eaton, No. 1,162,905, Dec. 7, 1915.

The principal objects of the present invention are to provide an improved device of the above type capable of performing the cutting operation rapidly, and to this end so constructed and arranged that the depth of cut is at least as great at the end of the operation as at the beginning; to provide a device capable of severing a pipe without undue exertion on the part of the user even though the outer surface of Vthe work be rough or eccentric; and having provision'for removing such burr as may be formed upon the interior of the pipe during the cutting operation.

In the accompanying drawings there is shown by way of example, a'preferred embodiment of the device of the present invention, and in such drawings Fig. 1 is a rear elevation of a pipe cutter constructed according to the present invention,fcertain portions being broken away; Fig. 2 is a front elevation of the cutter device, certain parts being broken awayl the cutter and depth gage being indicated in the relative positions which they occupy substantially vat the' beginning of the operation;

Fig. 3 is a view similar to Fig. 2 but showing the cutter and depth gage at a later stage of the operation; and

Fig. lis ak fragmentary edge view showing details of a reamer device associated with the cutter.

Referring to the drawings, numerals 1, 2 indicate respectively work-clamping jaws pivotally connected at the point 3. The jaw 1 is furnished with angularly disposed work-engaging surfaces f1, 5, while the jaw 2 is furnished with similar surfaces 6, 7, the several surfaces being of sufficient length to prevent twisting of the pipe clamped therebetween. A piece of pipe is indicated at'8 as secured between the engaging surfaces of the jaws.

A handle member 9 is pivotally secured at thepoint 10 to the jaw 2, such handle having a laterally extending arm 11jv T he outer end of the jaw 2 is provided with spaced Aears 12, 13, between which is positioned the end of a connecting link 111 pivotally secured to such ears by means of apin 15. This link'lat is screw threaded for a substantial portion of its length, as indicated at' 16, and

such threaded portion normally engagespa Y slot 17 formed in one end of a resilient plate 18 secured to the outer surface of the jaw A nut 20 has 1 by means of a screw 19. screw threaded engagement with the link 16, such nut having a rim. 21 constituting a hand wheel wherebythe nut may be turned.

Preferably the slottedouter` end ofthe plate 18 is bent slightly as shown at 22 in Y order to prevent the nut 20 from slipping therefrom. The link 16 and the nut 20 as thus arranged serve releasably to secure the jaws 1 and 2 in operative position. The arm 11 of the handle member is furnished with a shallow groove or slot in its front face, such groove having the substantially parallel side walls 23, 24 and the oblique end wall 25 convenientlyv formed by securing a filler piece 25a in the lower end of the slot. This groove serves for the reception of a cutter 26 of trapezoidal form, made with an opening 26a for the -reception of a screw 2Gb whereby it may be secured in position. The cutter is provided with cutting edgesv 27, 28 at its opposite ends, one of suchV cutting edges projecting. beyond the arm 11 and the other seating in the angle between faces 23 and 25.

A second shallow slot-or groove 29 is also formed in the front face ofthe arm 11, such slot having the parallel side walls'30, 31 respectively 'and constituting av guideway for a movable depth gage 32. i This depth gage is furnished with a work-engaging face 33 and with a lateral slot providing kanedge 34 which normally engages a cam surface 35 formed upon a rotary .shaft 36. This cam surface comprises va concentric portionv and an` eccentric portion 37, alternatively engageable with the edge 34k.` The shaft 36 is provided with a mutilated pinion 38 at the rear of the arm 11, such pinion meshing with a gear segment 39 secured to thefjaw 2. The shaft is retained in operative position by means of a cotter pin 4:0 extendingl through an opening in such shaft and'bearingy against the forward surface of a cover plate el secured by means of screws such as 42 against the Aforward surface of the arm l1 and serving to retain the depth gage32 inV operative positionin its guideway. conical reamer i3 is secured by means of a bolt 4d at any convenient point upon the han-` dle 9. Preferably, the arm 11 is scooped out at 4:5 at a point between the cutter 26 and the depth gage 32 to provi-de a bevelled surface for defiecting the chip' from the plane of the cut. The depth gage is also provided with a similar chip guiding surface at lo in its forward face.

In the operation of the device, the pipe 8 is clamped between the jaws l andv 2 in the Y manner above described, the handle 9 being serves to determine the depth to which the cutting edge 27 of the cutter may be forced into the pipe. The operator now seizes the handle 9 and swings the entire device in a clockwise direction about the axis of the pipe, thus carrying the cutter circumferentially about the piper and removing a chip of predetermined thickness therefrom. When the cutter has made a complete revolution about the pipe, Vthe depth gage then enters the groove formed by the cutter, thus permitting the cutter to move inwardly toward the center of the pipe for removing another chip. llt is evident that the handle -9 will swing slightly about its pivot point l0 as the gage moves radially into the pipe, but as the gage is at a greater distance from the pivotal point l0 than the cutter, the gage will tend to 'approach the axis of the pipe more rapidly than does they cutting edge of the cutter. Such action .would constantly tend todecrease the depth of cutas thel cuttingV operation progressed and in order to avoid this action, applicant has provided the cam arrangement abovedescribed for positioning the depth gage. As the handle 9 swings about its axis l0, the segment 39, engaging the pinion 3S, turns the shaft 36 so that the eccentric portion 37 of the cam is brought into engagement with the edge 34 of the gage. As the gage and cutter swing toward the work along arcs having different radii (that of the gage being the longer) the gage tends to approach the center of the work more rapidly-than the cutter so that if they ywere relatively fixed the normal differences in the distances of the cutter and gage from the center of the work would quickly decrease and the depth of cut would likewise diminish. By suitably calculating the cam` surface 37 the gage is allowed to Yre-V cede gradually relatively to the cutter1 so as exactly to compensate for the effect of their dieren't distances froniftlre axis l0 and thus the depth of cut is kept substantially uniform throughout the operation. Under some circumstances it may be found desirable to forni the cam surface 87 of such contour as to permit the gage to move outwardly at a greater rate than above described,v thus progressively increasing the depth of cut as the diameter of the pipe decreases. n

As the plate 18 vis somewhat resilient, the jaws l and 2 may spring apart slightly during the rotation of the cutting implement about the axis of the pipe, such action being highly desirable in view of the fact that pipe is frequently eccentric and has'a rough surface, so that with jaws rigidlyclainped Vtogether it would be very difficult, if not impossible, to swing the implement about the ililVhile the typ'e of cutter herein employed usually'produces but little burr, it is found that in some instances a slight burr may be formed upon the interior of the pipe and for removing this burr the Areamer device Y43 is provided, such device being conveniently arranged upon the handle 9 so that the handle may be employed in rotating the reamer for removing the burr from the interior of the ipe. Y

lllhat l claim and desire to secure by lietters Patent of the United States is:

l. A pipe cutter comprising work cla-mping means, a cutter, a depth gage, and means for automatically varying the position ofthe cutter and gage relatively to each other dur- Y ing the cutting operation.

2. A pipe cutter comprising work clamping jaws, a cutter, a depth gage, means for pressing said cutter and gage against the wor t, and means permitting the depth gage to move relatively to the cutter during the cutting operation'.

o. A. pipe cutter comprising work clamp ing means, a pivotally mounted handle member, a cutter fixed to said handle member.y a depth gage movably supported upon'said handle member, and means for automatically causing the gage to retract as the cutting operation progresses.

4. A pipe cutter comprising workholding means, a pivoted member having a cutter mounted thereon, a depth gage also carried by said pivoted member, said gage and cutter beingat different distances from the pivotal axis of said member, rand means for automatically permitting the gage to retract relativ'ely to the-cutter as the cutting operation progresses.

5; A pipe cutter comprising work holding means, a pivoted member having a cutter and depth gage mounted thereon, the cutter being arranged nearer the pivotal axis of Cil said member than the gage and having its cutting edge nearer the center of the worlr, in a radial direction, than the work engaging element of the gage, and means for automatically maintaining such difference in ra- Ydial distance as the cutting operation progresses. j

6. A pipe cutter comprising work holding means, a pivoted member, a cutter and a depth gage mounted upon said member, the cutter being nearer the pivotal axis of said member than the gage, and means operable during the cutting operation'for compensating for the greater arcuate movement of the gage about said'axis whereby to prevent de crease in the depth of cut during the cutting operation.

7. A pipe cutterl comprising meansfor holding the work, a pivoted handle member, a normally xed cutter secured to said member, a depth gage mounted upon said member and arranged to slide in a direction substantially radial of the work, said gage being at a greater distance from the pivotal axis of said member than the cutter, and means permitting said gage to move relatively to said handle member as the latter is actuated to move the cutter over the surface of the work.

8. A pipe cutter comprising work holding means, a pivoted member having a cutter mounted thereon, a depth gage slidable in a guideway in said member, cam means for determining the` operative position of the gage relatively to the cutter, and means for actuating such cam means in accordance with the movement of said pivoted member for insuring a uniform depth of cut'during the entire cutting operation.

9. A pipe cutting implement having work clamping means, a pivoted handle member, a cutter secured to the handle member, a depth gage mounted in a guideway in said handle member, a rotary shaft journalled in said handle member and having' a cam element engaging the gage for determining the position of the latter relatively to the cutter, a pinion fast to said shaft, and a relatively fixed gear sector meshing with said pinion for causing the latter to turn as the handle 4 member is actuated.

10. A pipe cutting implement comprising pivotally connected, work clamping jaws, handle member fulcrumed to one of said jaws, a cutter secured to said handle member, a depth gage slidable in a guideway in said member, said gage being at a greater dist-ance from the pivotal axis of the handle member than the cutter, a rotary cam bearing against said gage for determining its position relative to that of the cutter, a .gear sector fixed to the jaw upon which the handle member is fulcrumed, and a pinion meshing with said sector and transmitting motion to said cam as the handle is actuated whereby to permit the gage progressively to retreat along its guideway.

1l. An implement of the class described `comprising a pair of jaws, a handle pivoted to one of said aws, a cutter secured to said handle, and means, comprising a resilient plate fixed to one jaw, for connecting the free ends of ysaid jaws the resiliency of the plate permitting slight relative movement of said jaws. I

12. A cutting implement of the class described comprising a pair of jaws pivoted together', a cuttingk element supported by one of said jaws, and means comprising a resilient plate secured to one jaw Afor coni nectingk the free ends of said jaws during the operationk of the cutting element the resiliency of the plate permitting slight relative movement of the jaws.

18. A cutting implement of the class described comprising a pair of jaws pivoted tremity of one of said aws, said link having j an externally lscrew threaded portion and a nut engaging the same, and a resilient member secured to the other Vjaw and having a slot in itsv extremity for `the reception of the link and a surface with, which the nut mayv engage whereby to hold the jaws in operative relationship.

15. A pipe cutter comprising a` pair of `pipe engaging jaws pivoted together, a han.

dle pivotally secured to one of said jaws,V

said handle having a recess provided with parallel side walls and an end wall oblique with respect to such 'side walls, a double ended cutter lodged in said recess with one of its ends bearing against said oblique wall,

and a cover member for retaining thecutV ter in operative position. j

16. In combination with a handle menber, a cutter ixedly mounted upon the handle member, work clamping means pivotally secured tothe handle member, a depth gage morably mounted upon the handle member,

and means controlled by variations in relaf tive position of the handlerand clamping means for automatically retracting the gage as the cutting operation progresses.`

Signed by me at Boston, Massachusetts,Y

this fifth day of July, 1922.

HARRISON H. EATON. 

